A two-phase immersion cooling device includes an upper box body, a lower box body, a plurality of heating elements, and a condenser. The walls of the upper box body form a first cavity. The lower box body defines a second cavity containing coolant. The heating elements are disposed in the second cavity and immersing in the coolant. The condenser in the upper box body includes multiple rows and columns of condensing tubes, is arranged across or along the upper box body to fill the first cavity. The lower box body is detachably and hermetically connected to the bottom of the upper box body, connecting the second cavity with the first cavity to form an accommodating cavity.